Duplex pumping apparatus



1941- w. H. 'LANNERT DUPLEX PUMPING APPARATUS Filed Oct. 26, 1939 Patented Dec. 9, 1941 UNITED. STAT E'S PATENT OFFICE DUPLEX PUMPING APPARATUS I William H. Iannert, Chicago, Ill., assignor to Chicago Pump Compan poration of Illinois y, Chicago, 111., a, c

Application October 26,1939, Serial t. 301,386

9 Claims. (c1. 103-3) This invention relates to duplex pumping apparatus and in its present form it has been designed for ejecting sewage. Usually a single inlet pipe or conduit is provided for the two pumps of the apparatus, which inlet pipe connects through a fitting with both pumps. Heretofore it has been found that paper, rags, fibrous and other solids collected in the fitting and clogged the passages therethrough, and one of the objects of the present invention is to eliminate clogging of the fitting.

Another object is to provide a duplex pumping apparatus in which rags, papers, fibrous and other solids are passed freely to certain strainers disposed .in the discharge lines of the pumps,

which strainers prevent solids from entering the pumps and interfering with their operation.

Ordinarily the pumps are operated alternately to eject sewage from a basin, and either one of the pumps is usually at rest. During the operation of the running pump it pumpsliquids back through the strainer associated therewith, thereby flushing it and dischargingthe collected solids along with the liquids. Y r

Another object is to pro'vide'a fitting of novel construction wherein the liquids which enter the fitting wash all of the solids out of the fitting, thereby preventing clogging thereof.

Another object is to provide an inlet fitting The invention is clearly illustrated in the draw-, ing accompanying this specification, in which:

Fig. 1 is a side elevation of a duplex pumping apparatus embodying a simple'form of the -invention, and showing the same applied to a basin which is illustrated in vertical section;

Fig. 2 is an elevation of the apparatus looking in the direction ofthe arrow 2 in Fig l, and showing the basin in vertical section; 4

Fig. 3 is a detail elevation of one embodiment of the fitting upon an enlarged scale, looking in the direction of the arrow 3 in Fig. 1. a

Fig. 4 is a detail vertical cross section taken on the line 4 -4 of Fig.3, and

Fig. 5 is a vertical cross section taken along the irregular dotted line 5-5 of Fig. 4.

Referring to said drawing, which illustrates one embodiment'of the invention, the reference character '6 designates a receptacle in which'the duplex pumping apparatus is contained. In accordance with the application of the invention illustrated, the receptacle is in the nature of a j basin, although it may take the form of a dry pit associated with a basin, as is stood.

Duplex pumps 1, 8, preferably of the centrifue galtype, are supported adjacent the bottom of the receptacle by hanger pipes ,9, which are carried by the cover III for the receptacle. Electric motors ll, l2 are mounted on motor bases l3, l4, supported-by the cover I 0, and their motor w :1l undershafts (not shown) are connected to the impeller shafts l5 of the pumps in the usual manner well known to those skilled in theart to which this invention pertains.

The suction inlet of each" pump is through'a suction plate lfi'located at the bottom of each pump case, and the discharge is throughavolute l6a, to which is connected a strainer ll of con--v ventional form, the upper end of which is connected by a T fitting l8 with a discharge pipe Ill. The discharge pipes usually lead up through the cover and are connected by suitable fittings to discharge pipes (not shown) which carry away the ejected sewage. When the pumpingapparatus is used in a dry pit, the suction inlets of the pumps are connected by suitable pipes or" conduits with derstood. I

An inlet pipe or conduit 20, common to both pumps, leads from the source of supplyto the receptacle 8, and its end is connected to a fitan associated basin as is'well unting 2| bolted or otherwise fastened to a wall of the receptacle. Desirably the fitting is composed .of a single cored casting, and is formed with a bolting flange 22.0n one side, bolt-ed to a wall of the receptacle and having a hub 23 on its outer side containing an inlet opening 25a, in which the end of the inlet pipe is received. Any suitable form of joint may be provided between the inlet pipe and hub of the fitting.

The wall 24 of the main body or the fitting.

provides a chamber 25 having a bottom, whose wall 21 is desirably of concave or other desirable shape',.merging into the upright wall of the main body portion. Desirably the wall 24 of the body trolled automatically. means are provided for starting and stopping the I is. curved and merges into the bolting flange 2:

and hub 23.

In opposite sides of the wall 2! above its bottom. two outlet openings, 28. are formed, and

extending from the two sides of the wall 24 around the openings 23 are two hollow branches .29 that lead to a bolting flange 30 through which the branches open out as at 3|. 7

From an inspection of Fig. it will be seen that the chamber communicates with the inlet opening 25a of the fitting near the upper end of the chamber, and that the latter communicates with the two branches at places above the bottom of the chamber through the opening 28,

Liquids spilling into the chamber fall upon the the branch through which the liquids are flowing.

Each outlet 3| of the branches is connected to an associated discharge pipe l9=by suitable connections, whereby the incoming liquids and solids may pass to the discharge pipe and through the strainer, where the solids are intercepted, and the strained liquids may flow through the pump and and both pumps act to elect the liquid. When the low level is again reached, both pumps. are

' solids; thence through the connections to'the discharge therefrom through its suction inlet,

into the basin.

As shown, the connections just mentioned may comprise gate valves 32, one for each branch of the fitting, and bolted to the bolting flange of the fitting, pipes or other conduit 33 connected to the gate valves and check valves 34, one connecting each pipe 33 with one of the T fittings 18. flow through the pipes or other conduits 33.

Desirably a strainer 35 is secured to the open top of the fitting, through which liquids may escape in the event that the liquid enters the receptacle faster than one pump can discharge it therefrom.

The switches for the motors may be manually operated, if desired, to run the pumps alternately, but it is preferred to have their operation con- For this reason suitable pump motors and for startingthem in alternate sequence. 'I'hemeans shown comprises float operated electric switches 36. of which the floats 31 are. located in the receptacle or in the basin,

if a separate basin is used to receive the liquids ternating means 40 is provided whereby the pump motors are started alternately. Various forms of alternating devices maybe used, an example of which is that shown and described in the A. C. Durdin, Jr. Letters Patent No. 1,666,873, dated April 17, 1928, for a Duplex pumping apparatus.

In this apparatus one float mechanism, to-

The check valves open in the direction of discharge pipes, down through the strainers, where the solids are intercepted, and the strained liquids pass through the volute discharge ends of the pumps, into the latter and out through the suction inlets thereof, into the receptacle, or into a separate basin, if one is used.

When the float mechanism which is set to 0D- erate first, is raised by the accumulated liquids which have risen to the-pre-determined level, it trips the electric switch for the motor which is to start first. The pump of that motor starts, thereby discharging liquid from the basin through thestrainer associated with-it, the liquid carrying the collected solids with it and discharging through the associated discharge pipe. Pressure being set up in the discharge pipe, the check valveassociated therewith closes, preventing back flow through the connections with the fitting. Liquid which continues to flow into the fitting from the inlet pipe, flows through the branch of the fitting that connects with the idle pump, through the associated connecting pipe, check valve and T fitting, through'the strainer, and through the idle pump into the receptacle as has just been explained.

With one pump in operation liquids may continue to flow into the fitting from the inlet pipe and pass through both branches and both connections, 33, but inasmuch as the check valv in one connection to the discharge pipe of the pump which is in operation is closed, that branch from the fitting will fill, and then the flow will be through the other branch to and through the connections33, strainer and idle pump and into the receptacle or basin. Rags, paper, string and other solids carried in the liquids fall into the concave bottom of the chamber as indicated by I 1. In pumping apparatus which employs an inlet pipe, duplex motor driven pumps and discharge pipes therefor, a non-clogging inlet fitting having upright and bottom chamber walls providing an upright chamber having a bottom, and

- having an inlet opening adjacent its upper end gether with its alternating device, operates to start one pump motor when the liquid reaches a pre-determined high level and stops the motor when the liquid reaches a low level, and when the liquid again reaches the high level the other float mechanism starts the other pump motor and stops it when the liquid reaches the low level. In case the 'liquid accumulates faster than one pump can eject it, the idle motor is then cutin ,connectedto said inlet pipe, said fitting having other walls providing two hollow branches which open from the chamber at places below the inlet opening and above the bottom of the chamber, said branches being connected respectively to said discharge pipes.

2. In pumping apparatus which employs duplex motor driven pumps, a common inlet pipe therefor, and discharge pipes therefor, a non- Y clogging inlet fitting comprising an upright wall said fitting having also other walls providing two hollow branches which extend from the sides of the upright wall and are connected respectively to said discharge pipes, each branch opening at one end to said chamber below the inlet opening with the lower edge of the branch opening to the chamber above the bottom of the chamber to leave a pocket therein below the lower edges of the branch openings to the chamber.

3. In pumping apparatus which employs duplex motor driven pumps, a common inlet pipe therefor, and discharge pipes therefor, a nonclogging inlet fitting comprising an upright wall and a concave bottom wall merging into the upright wall, said walls providing an upright chamber having an inlet opening disposed above its concave bottom and communicating with said inlet pipe, said fitting having also other walls providing twohollow branches connected respectively to said discharge pipes, which branches extend from the sides of the upright wall, each branch opening at one end to said chamber below the inlet opening with its lower edge disposed above the concave bottom of the chamber to leave a pocket therein below the lower edges of the branch openings to the chamber.

4. In duplex pumping apparatus, a non-clogging inlet fitting consisting of a cored casting comprising an upright wall and a bottom wall which provide an upright chamber having an inlet opening adjacent its upper end and a bottom located therebelow, the fitting being formed with other walls providing hollow branches which open at one end to said chamber through openings in its upright wall, the lower edges of the openings from the chamber to the branches being located above the bottom of the chamber to leave a pocket below said lower edges, and said branches having outlets at their other ends.

5. In duplex pumping apparatus, a non-clogging inlet fitting consisting of a cored casting comprising an upright wall and a concave bottom wall merging into the upright wall, said walls providing an upright chamber having an inlet opening adjacent its upper end and a concavebottom located therebelow, said casting having other walls providing hollow branches which open at one end to said chamber through openings in its side wall, disposed above the concave bottom wall, said branches having outlets at their other ends.

6. A fitting consisting of a hollow casting comprising an upright wall and a concave bottom wall forming an upright chamber having an inlet opening adjacent'its upper end and a concave bottom, said casting having other walls providing two hollow branches which extend from the upright chamber wall and .open to the chamber below its inlet opening, with the lower edges of the branch openings disposed above the concave bottom of the chamber, said branches having outlets at their other ends and bolting flanges, one merging into the upright chamber wall and having the inlet opening therein and the other flange merging into the outlet ends of the branches.

'7. A fitting consisting of a hollow body comprising an upright wall and a concave bottom wall forming an upright chamber having a concave bottom, there being an inlet opening adjacent the upper end of the chamber and two outlet openings through the upright chamber prising an upright wall and a concave bottom wall which provide an upright chamber having a concave bottom, there being an inlet opening to the chamber adjacent its upper end and two outlet openings which open through the upright chamber wall below the inlet opening and above the concave bottom of the chamber, said fitting having other walls providing two downwardly directed hollow branches, said last mentioned walls joining the upright chamber wall around said outlet openings.

9. In duplex pumping apparatus which employs duplex motor driven pumps, a common inlet pipe therefor and discharge pipes therefor, a non-clogging inlet fitting comprising an upright wall and a concave bottom wall merging into the upright wall, said walls providing an upright chamber having a concave bottom, other walls extending from two opposite sides of the upright wall and providing two hollow branches, each branch leading from the chamber through an opening in its upright wall with the lower edge of each opening located above the concave bottom of the chamber, whereby to leave a pocket therein below the lower edges of the branch openings to the chamber, said upright wall having an inlet adjacent its upper end disposed above the branch openings to the chamber and connected with the inlet pipe, and the other ends of the branches having connections respectively with the discharge pipes.

WILLIAM H. LANNERT. 

